Some electric toothbrushes known at present comprise a brush similar to those for hand toothbrushes but generally smaller in size than the ones most usually used, to which a small electric motor supplied by battery, accumulator or power plug, imparts an oscillating, jerky, generally reciprocal movement which is more or less complicated.
The brush may also be rotated continuously about a longitudinal axis to avoid contact between the brush and the tissues which have no need to be brushed (cheeks, tongue, palate . . . ), this brush being often surrounded, over about a third of its periphery, by a coaxial gutter.